Printing mechanism



May 19, 1964 D. TRINGALI PRINTING MECHANISM 2 Sheets-Sheet 1 Filed July 20, 1962 INVENTOR DOM/NICK TR/NGAL I BY jflfixma ATTORNEY May 19, 1964 D. TRINGALI PRINTING MECHANISM 2 Sheets-Sheet 2 Filed July 20, 1962 /N VEN TOR DOM/NICK TR/NGAL/ A 7'7'ORNEY United States Patent 3,133,499 PRINTING MECHANISM Dominick Tringali, Litchfield, Conn, assignor to General Time Corporation, New York, N.Y., a corporation of Delaware Filed July 20, 1962, Ser. No. 211,273

8 Ciaims. (Cl. 101297) I This invention relates to a print mechanism and more particularly to a print hammer mechanism for printing indicia upon a card when the card is inserted therein.

In one preferred embodiment the print hammer of the instant invention is arranged to float resiliently in a substantially dead-center position. Upon insertion of a card into the machine, a snap-action switch is closed which directly energizes an electromagnet whereupon the print hammer is drawn below its normal, dead-center position against the urge of a centering spring. After a predetermined downward travel an extension on the print hammer frame is instrumental in allowing the snapaction switch to open and the electromagnet de-energizes. The centering spring then acts to return the print hammer to dead-center position but the sharp action generated by the cocked centering spring causes the hammer to overtravel home position and effect a single imprint. The hammer then settles back to the dead-center position.

There are many mechanisms of different design for printing upon a card when the card is inserted. A very popular usage is in time clocks for checking workers in or out of a plant, ofiice or warehouse. In these time clocks raised numbers on the rims of a row of clockdriven parallel disks, called print wheels, are used to print date and time indica. The numbers are first inked by a separate ink applicator or else an inked tape is positioned immediately adjacent the print wheels. The paper or card to be imprinted is then inserted into, a slot adjacent the print wheels, and the paper or card is sharply rapped against the print wheels by a striker hammer to cause printing. The art is crowded with such printing mechanisms and the usual known practice is to mechanically latch the print hammers in home position and then provide additional mechanism for unlatching then again relatching to control a printing operation.

However, applicant is aware of one printing device which is free of the usual mechanical latching and unlatching aspects. This device efiects imprint when a card is manually entered therein and is somewhat comparable in design to applicants. Briefly outlined, insertion of a card in the known device energizes an electromagnet through a series connected double switch arrangement whereby the electromagnet armature is withdrawn against the urge of two springs. The armature has a pendant rod fixed therewith which loosely fits in a separate hammer block located adjacent the print wheels. As the armature withdraws the springs attached on either side thereof stretch and the pendant rod is partially withdrawn from the recess in the hammer block. An extension fixed on the armature opens one of the series connected switches as the armature continues to be withdrawn whereupon the circuit to the electromagnet is broken. De-energization of the electromagnet releases the armature to the force of the armature springs. Shortly thereafter the pendant rod sharply strikes the hammer block after some free travel and impels it against the card and print wheels. The print hammer then settles back to rest against a positive stop.

In such a print mechanism of the type outlined there is no suggestion of an over-center action; the hammer and armature are separate units; a metal to metal collision is established during a print operation. Furthermore, erratic performance is often experienced if the two switches employed are not accurately adjusted. Slight Patented May 19, 1964 misadjustment causes duplicate or strike-over printing upon each insertion of the card. In such arrangement an arc suppressor is needed for each switch. Also, the indicia are frequently printed out of line due to premature or late actuation of the mechanism. In other instances the mechanism may jam, or it may print even after the card has been removed. Occasionally the machine runsaway; i.e., continues to print rapidly though the card has been removed. Moreover, printing mechanisms that latch or arrest their hammers and then impel them from a dead or stationary position are comparatively expensive and characteristically noisy. Obviously, these are all undesirable attributes.

Accordingly, an object of this invention is to provide a novel, dependable and very economical structure for a print mechanism.

Another object is to provide a printing mechanism which features a suspended print hammer free of mechanical latching.

A further object is to provide a print mechanism characterized by an over-center action and use of a single spring.

A still further object is to provide a print mechanism that requires a minimum of force to condition the print hammer to eifect printing.

A still further object is to provide a print mechanism which is electrically actuated and employs a single snapaction switch whereby the need for are suppressors is eliminated.

A further object is to provide a print mechanism of the above character which has a unitary hammer head with hammer actuator and a unique positive-stroke printing action.

A still further object is to provide a print mechanism of the above character which prints automatically upon full length insertion of a print card or by manual operation upon partial entry thereof.

Another object is to provide a print mechanism of the above character which avoids duplicate or strike-over printing.

Still another object is to provide a print mechanism of the above character which will not jam or run away.

Other objects of the invention will in part be obvious and will in part appear hereinafter.

The invention accordingly comprises the features of construction, combination of elements, and arrangement of parts which will be exemplified in the construction hereinafter set forth, and the scope of the invention will be indicated in the claims.

For a fuller understanding of the nature and objects of the invention, reference should be had to the following detailed description taken in connection with the accompanying drawings, in which:

FIGURE 1 is a perspective view of a preferred structural embodiment of the print mechanism of this invention,

FIGURE 2 is a front end view showing the positioning of the print card with respect to the print wheels and the hammer,

FIGURE 3 is a perspective view of an alternate structural embodiment of this invention,

FIGURE 4 is a front elevational view, substantially along lines 44 of FIGURE 3, wherein the members shown in solid lines are at rest position and those in dot and dash lines are in fully cocked position prior to effecting a printing stroke.

FIGURE 5 shows a modified circuit arrangement whereby only a single energization of the electromagnet of the invention is possible during a printing stroke.

Similar reference characters refer to similar parts throughout the several views of the drawings.

Imprinting mechanisms of the type disclosed herein and others, it has been fairly well established that the most effective manner in which to print is by pre-loading or cocking a spring. The conventional procedure heretofore employed was to mechanically latch a springloaded unit and then release the latch to accomplish a printing stroke. As will become more readily apparent, the apparatus of the instant invention eliminates the need of mechanical latching the print producing unit. More specifically, in the present invention the print hammer is suspended or floats freely; hammer frame arrestl ing or latching against a solid stop is pointedly avoided.

As seen best in FIGURE -1, the print mechanism of this invention broadly consists of a hammer frame 19, which is resiliently positioned along a center line 11 in its normal rest position. Upon cnergization of an electro-magnet hammer attracting means 12, the hammer frame is moved off center against its resilient center line positioning means 20 into a cocked position as shown by the dotted lines 13 in FIGURE 2. Upon deenergization, the hammer, due to its resilient support means, snaps back toward its rest position, but in so doing, it over-travels and punches the print card 14 against the print'means.

More particularly, the print mechanism consists of hammer frame 10, which is resiliently supported along a center line extending between fixed hammer pivot shaft 4% and hammer frame spring 29. This pivot shaft-spring arrangement provides a resilient support for the hammer assembly which is positioned adjacent to but spaced from a set of print wheels 22. The print wheels, in this instance, bear date and time indicia on their rims. These indicia are continuously being adjusted by rotation of the print wheels by a time recording apparatus (not shown) so that an accurate date and time printing will occur upon each insertion of the record (or time) card 14.

The card 14 is inserted into the space or slot 15 (FIGURE 2) between the hammer and the print wheels. An underlying card platform 16 guides the card in its fully inserted position. When it reaches a certain depth of insertion, the lower edge of the card 14 actuates a switch 24, which supplies current to an electromagnet 2-6. The magnetic force generated moves the hammer frame it off its center line 11, in this instance toward the magnet 26. As the hammer travels downwardly, a release mechanism comprising a set of levers, one of which is operatively coupled to the hammer, acts to deenergize the magnet 26. When de-energized, the hammer frame It) is released, and it sharply snaps back toward its rest position.

The sharp snap action is generated by the high modulus of spring 20. In snapping back to its rest position, the hammer head 54 overtravels to punch print card 14 against the protruding indicia on print wheels 22, acting through an inked or carbon ribbon 23. The card is thus printed with date and time indicia. Duplicate printing of the card does not occur even though some additional oscillation of the resiliently supported hammer may occur. Duplicate printing is avoided because the oscillations of the hammer frame 10 are sharply damped by reason of the high modulus of spring 20.

As a consequence, the mechanism of this invention effects a singular positive hammer-blow print action. By the proper selection of a spring having a reasonably high modulus, the oscillation of the hammer when released can be almost immediately damped so that no strike-over occurs. Furthermore, run-away is impossible because the electromagnet has already been de-energized and there is no force to recock the print hammer. Other features will be evident from the detailed description which follows..

Hammer Assembly As seen in FIGURE 1, the print mechanism includes a hammer frame it), of a general U-shaped configuration having stepped arms 44 and 46. The free ends of the stepped arms 44 and 46 are pivoted upon hammer pivot shaft 48 which is secured to side frame portion 49 of the time recorder. An armature 50 is secured to the steps of the arms 44 and as by screws 52. The armature is made of a magnetic material, i.e., a magnetically soft, high reluctance material, for attraction by the magnetic field generated by the electromagnet 26. Thus, the hammer frame will be caused to move off-center into a cocked position (dotted lines 13 in FIGURE 2), when the electromagnet is energized.

It might be here noted that an alternate but equally effective structure could be formed by positioning the armature on a rearward extension of the hammer frame 10. This would also require repositioning of the electromagnet 26.

The bight portion of the U-shaped frame 10 supports a hammer head 54, which may be of hard rubber or the like, via two rivets 56. Extending away from the bight portion of the frame is a spring anchor 58 to which is secured the hammer frame spring 20, its other end being secured to a rod 21 which is fixed in side frame 49. The hammer frame spring 20 is preferably one having a high modulus or spring constant so that it will act to immediately damp any oscillation of the hammer. This arrangement of hammer frame 10, pivoted on shaft 48 at one end and spring supported on its other end by spring 20, provides a resilient center line suspension for the hammer assembly. Thus, the hammer is stilfly but resiliently suspended along center line 11 (FIG. 2). When the electromagnet 26 is energized, the hammer will be moved offcenter into a cocked position (dotted lines 13 in FIG- URE 2). Upon release by de-energization of the electromagnet, the spring 24) will jerk the hammer back toward the center line 11, but in so doing, the inertia of the hammer will cause it to travel past the center line and strike time card 14, which has been inserted in slot 15 between the hammer head 54 and the print wheels 22. Only one blow will occur because the high modulus of the spring utilized will act to sharply damp further oscillation of the hammer.

Secured to the near side of the U-shaped hammer frame it is a switch lever knock-off finger 60. Its function will be described in greater detail below with reference to the release mechanism.

Hammer cocking Means As seen in FIGURES l and 2, the hammer cocking means 12 consists of an electromagnet 26 supplied with current by wires 64 and 66 via switch 24. Electrical potential is supplied to wires 65 and 66 when plug 67 is connected. Wires 64 and 65 are coupled upon closure of switch 24. Electromagnet 26 is positioned on one side of the hammer frame (the lower side in FIG- URES l and 2) and when energized it acts to draw the armature 5t downwardly.

It might here be noted that although FIGURES 1 and 2 illustrate the electromagnet 26 as being below the horizontally positioned hammer assembly, vertical or even oblique positioning of the assembly with appropriate shifting of the electromagnet is also possible.

Switch 24 is connected in series with the electromagnet 26 and is preferably of snap-action type having a lostmotion characteristic. Accordingly, when such a switch is operated it will actuate to a definite make condition then open when the actuating member is removed, as is well known. Such actuation prevents any chattering effects. The switch is closed by a sliding switch lever 70 through a laterally extending switch-operating tab 72 formed from lever 70, as shown. The switch lever is pivoted at, 74 to a card-engaging lever 76. The upper end of the card-engaging lever 76 has a card-engaging tab 77 which is engaged by the edge of the time card 14 when it is fully inserted. Lever 76 is pivoted on a stud which is secured to a fixed pivot support 82. The support extends forwardly (in FIGURE 1) from the time recorder frame portion 49. A spring 78 attached to lever 70 maintains levers 70 and 76 biased to the FIGURE 1 position. Clockwise pivotal movement of lever 70 being limited by switch blade 25 overlying lever 70.

The Hammer Release Mechanism The hammer release mechanism includes the switch lever 70, the spring 78 and switch lever knock-off finger 68.

Lever 70 is normally biased clockwise about pivot 74 and abuts switch blade 25 while lever 76 is normally biased counterclockwise about pivot 80 (as viewed in FIGURE 1) by switch lever spring 78. Such arrangement causes tab 72 to engage and close switch 24 when the time card 14 is fully inserted into slot 15 and lever 76 actuates clockwise. Now, as the hammer assembly travels downwardly in response to the magnetic attraction of the electromagnet 26 to a cocked position, the switch lever knock-off finger 60 engages lever 70 and pivots it counterclockwise about pivot 74 against the urging of spring 78. .This knocks tab 72 below a switch blade 25 of switch 24 and the switch opens. The electromagnet is thereby de-energized. The cocked hammer head 54 is released and it travels with great force past center line 11 to punch the time card 14 against the print wheels 22. Repeated punching does not occur because the stiff hammer cocking spring has such a high spring constant that it damps further oscillation ofthe hammer.

It should here be pointed out that slight movement of the card 14 in and out will have-no effect on switch 24 at this time. More specifically, when finger 60 lowered tab 72 below switch blade 25, switch 24 opened, electromagnet 26 de-energized and operating tab 72 remained below blade 25. Printing occursimmediately thereafter and as card 14 is withdrawn from tab 77 of lever 76; spring '78 returns the mechanism to the position illustrated in FIGURE 1.

Operating Sequence A time card 14 is first inserted into slot 15 between print wheels 22 and hammer assembly 10. Upon reaching almost to the depth of the slot, the lower end of the time card contacts tab 77 and card engaging lever 76 pivots clockwise about stud 80 (as viewed in FIGURE 1). Such pivotal action causes switch lever 78 to move to the left whereby tab 72 contacts blade 25 and closes switch 24. Current is thus supplied to the electromagnet 26 and the hammer assembly 19 is drawn downwardly into a cocked position (shown in dot and dash lines, FIG- URE 2). During downward travel of the hammer assembly, the switch lever knock-elf finger 60 forces switch lever 7 0 to pivot about pin 74 against the force of switch lever spring 78. This knocks'tab 72 below switch blade 25 so that the switch opens, whereby the electromagnet 26 de-energizes. Spring 78 holds tab 72 up against the lower surface of the switch blade 25 until the card is removed.

De-energization of the electromagnet causes the hammer spring 20 to forcibly return the hammer assembly 10 to its rest position. However, due to momentum, the hammer head 54 travels past the center line position of the assembly represented by line 11, see particularly FIGURE 2. The hammer head 54 thus punches the time card against the ink ribbon 23 and the indicia on the print wheels 22. The card is thus printed with date and time indicia currently facing the card. Further printing is prevented by the inherent damping force of spring 20.

Upon removal of the card, return spring 78 returns '6 is desired to print upon a card without full insertion thereof, the below described mechanism may be put to use:

For example, if the material to be printed on lacks the rigidity to operate or trigger lever 7 6, a manually operable lever plate is depressed whereupon it pivots clockwise (FIGURE 1) about a pair of studs 86, only one of which is shown. Such action moves a rod 87 to the right against the urge of a compression spring 90, mounted on rod 87 and contained between a collar 92 fixed on rod 87 and side frame 49. Lever 76 is bifurcated as at 94 to receive a turned down portion of rod 87 with a shoulder 96 threreof in proximity to bifurcation 94. Spring 78 normally holds the relationship of shoulder 26 with bifurcation 94, as shown in FIGURE 1.

Thus it should be readily apparent that manual depression of plate 85 moves rod 87 to the right and pivots lever 76 clockwise. Thereafter the same sequence of part movements occur and printing is effected in the same manner as described in connection with card triggering.

When pressure is withdrawn from lever plate 85, spring 98 returns rod 87 and plate 85 to the FIGURE 1 position.

The turned down portion of rod 87 and bifurcation 94 are so arranged that lever 76 operates independently of rod 87 during card triggering.

The modification shown in FIGURES 3 and 4 illustrates an alternative manner to effect printing Without the use of expensive latching means by utilizing a single switch and hammer actuating spring. In this embodiment, the spring is of a multiple-volute or torsion type commonly known as a wrap-around spring. The switch is of the same type as explained in connection with FIG- URES l and 2.

Referring now to FIGURES 3 and 4, a shaft 101) is supported in side frames 1112, only one of which is shown in FIGURE 3. Shaft 1150 supports a hammer frame 104 for pivotal movement. The hammer frame 104 is normally biased to the position shown in solid lines of FIG- URE 4 by a wrap-around spring 106. Spring 106 mounts on shaft 101 and has a pair of legs 107 anchored in an electromagnet support frame 108. Spring 1% has a hammer frame biasing end 110 extending forward, through a cut-out 112 in the hammer frame. Electromagnet 109 is fixed to its frame 188 which in turn is rigidly secured to the side frame 102 by screws 111, two of which are shown in FIGURE 3. The biasing end 110 of spring 106 is formed upwardly at its extreme forward end and has mounted thereon a bumper 114 which may be of yieldable material such as rubber, for example. End 110 of spring 106 engages the underside of hammer frame 164, as in the solid line position shown in FIG- URE4.

The hammer frame 104 has a bent down tab 118 that mounts a stacked armature unit 120. Upreaching arms 112 of the armature stack 120 support a printing hammer head of hard rubber or the like, as by rivets 126 (FIGURE 3). Hammer head 125 in normal position underlies a card platform 116, more specifically an opening 127 thereof. When a record card 128 is fully insorted into the machine, hammer head 125 is situated directly beneath a set of print wheels 130 having particular type aligned with the area to be printed on the record card 128. When the electromagnet 109 is energized, in a manner to be explained, the armature stack 12!) supporting hammer head 125 is drawn downwardly by the magnetic field generated in electromagnet 189 and spring 106 is cocked, as shown in dot and dash lines of FIGURE 4. Upon de-energization of electromagnet 169 (also to be explained), spring 106 is free to uncock whereupon it carries hammer frame 104 upwardly with considerable force. Thereafter, bumper 114 engages the underside of card platform 116 after traveling from the dot and dash to the solid line position of FIGURE 4. However, due to the considerable thrust given to the hammer head 125 it continues on upwardly and moves the record card 128 into engagement with the print wheels 130 which overlie an inked or carbon ribbon and a single printing is effected on the record card.

A print triggering lever 13?; is mounted at its lower end for pivotal movement on a shaft 134 fixed between the side walls (not shown) of the machine. Lever 132 mounts a record card engaging block 1136 at its upper end. Pivotally and adjustably mounted at approximately the central portion of triggering lever 1.32 is a switch lever 13% which is suitably spaced from lever 132, as shown in FIGURE 4. Switch lever 33 has a tab 139 offset therefrom which underlies the armature stack 12% and a second tab 140 oppositely offset from tab 139. Tab 14% has an elongate slot formed therein which accommodates a rod 142 that acts as a guide during horizontal and vertical movement of switch lever 13-8. A spring 144 urges levers I32. and 138 to the positions shown in FIGURE 3. Offset tab 140 has fixed thereto a substantially square member 146 which is arranged to engage the fiat area of a blade 148 extending from a snap-action switch 150, as shown.

In Operation Uponfull insertion of the record card 128, triggering lever 132 is pivoted counterclockwise (FIGURE 3) when card 128 engages block 136. Only a slight pressure need be exerted on card'll28 to effect such pivoting due to the obvious leverage advantage established by the mounting of lever 132. As trigger lever ldzpivots, switch lever 138 slides to the left, both movements against the urge of spring 144. Member 146 on tab Mi of switch lever 138 then engages switch blade 148. After some free travel of switch blade 148, switch 159 closes with a snap-action and connects wires I53 and 15 which then complete a circuit to electromagnet Ni via wire 155, see FIGURE 4. The hammer frame 164 is then drawn downwardly toward the armature attracting means 1211 to the position shown in dot and dash lines and spring 1% is cooked. Substantially at the position shown, the armature stack 120 engages tab 139 and depresses lever 138 whereupon member 146 is lowered beneath blade 14% of switch 159. The switch blade 143 is normally urged to the open or FIGURE 3 position, and when member 146 lowers beneath the blade, switch 150 opens. Blade 148 now is situated above member 146, switch lever 138 being held in the leftward position by the record card 128 holding trigger lever 132 in the pivoted position.

Deprived of electrical potential when switch 156 opens and separates wires 153 and 154, the electromagnet M99 now de-energizes. Spring 1% is now free to uncock whereupon it carries the hammer frame 194 upwardly with considerable momentum. When bumper 114 on spring 196 encounters card platform 116 its upward travel is restrained, but hammer head 125 continues on and impels card 123 into the print wheels with a sharp, snapping blow which causes a clear imprint. The hammer frame 104 then settles back to home position after experiencing some short oscillations but with no further printing or no ill effects.

If the card 128 is held fully inserted in the printing slot, trigger lever 132 remains in pivoted position and switch lever 138 remains in its rearward position. Switch blade 143 overlies its actuator, member 146. It can be readily understood that the switch 154) cannot be closed nor the electromagnet energized so long as this condition exists. No further printing can take place until the card is removed from block 136.

When the card is removed, spring 144 pulls switch lever 138 upwardly and to the right which action causes lever 132 (through its pivotal connection with lever 138) to pivot clockwise. Concurrently, member 146 is positioned to the front of switch blade 148 (FIGURE 3) and ready to set off a second print operation.

FIGURE discloses, schematically, a modified circuit arrangement for restricting the electromagnets of the invention to a single energization during a printing strike by incorporating a circuit restricting relay therein.

For convenience, the modified circuit will be explained in connection with the mechanism shown in FIGURES 3 and 4 but it is to be understood that such arrangement readily lends itself to the apparatus of FIGURES l and 2.

Referring now to FIGURE 5, when the card 128 is fully inserted switch 150 closes (as above described) and connects wires 153 and 154. A circuit is then completed to the electromagnet 109 via wire 155 and a source of electrical potential. Armature stack 120 is then drawn downwardly and cocks spring 106 (FIGURES 3 and 4) and also transfers a switch blade 157 of a relay 158. Blade 157 is normally biased to the position shown in FIGURE 5. Transfer of switch blade 157 connects a wire 159 with wire 155 and completes a circuit to energize relay 158 via wire 154, now closed switch 150 and wire 153. Upon energization relay 158 provides its own holding circuit via blade 157 and in turn maintains the circuit to electromagnet 109 open so long as card 12% holds switch 150 closed. Upon removal of card 123, switch 150 opens, relay 158 then drops out of circuit and permits blade 157 to re-establish the potential circuit to electromagnet 109. A new printing operation can now be initiated.

From the detailed description above, it should be seen that the mechanisms described effect a positive, quick print action upon a time card when inserted into the printing slot. Further, by reason of deactivation of the electromagnet prior to printing, only a single print will occur. There will be no strike-over or duplicate printings. Also, because there is only one activation of the electromagnet, the mechanism cannot jam or run away.

While the mechanism has been described with particular application to a time card and a time recorder, other printing and stamping applications are also possible.

Furthermore, while the spring suspension in FIGURES l and 2 extends horizontally between pivots 48 and 21 it is conceivable that the hammer frame it) may be suspended by springs oifset at right angles from pivot shaft 43 and the hammer frame without departing from the spirit of the invention.

It will thus be seen that the objects set forth above, among those made apparent from the preceding description, are efficiently attained and, since certain changes may be made in the above construction without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

It is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention herein described, and all statements of the scope of the invention which, as a matter of language, might be said to fall therebetween.

Having described my invention, what I claim as new and desire to secure by Letters Patent is:

I claim:

1. A print mechanism for printing indicia upon a record card when the card is inserted into the mechanism comprising, in combination, a pivoted hammer assembly including a magnetic-responsive armature and a hammer head integral therewith, spring biasing means for resiliently maintaining said hammer head in an unlatched and suspended center position, hammer head cocking means for effecting a cocking stroke comprising an electromagnet disposed to move said head off its center position against the force of said spring biasing means into a cooked position, switch actuation means responsive to insertion of said card for energizing said electromagnet,

disposed thereto that upon release of said hammer head from said cocking means said hammer head springs past its normal center position by the force of said biasing means to punch said card against said print means.

2. The print mechanism of claim 1 wherein said switch actuation means comprises a switch in series circuit with said electromagnet and levers operatively connected to said switch and said mechanism whereby upon insertion of said print card into the mechanism, said switch will be closed.

3. The print mechanism of claim 1 wherein said switch actuation means comprises a switch in series circuit with said electromagnet, switch levers operatively connected to said switch, and a manually actuated lever operatively connected to said switch levers for closing said switch.

4. A print mechanism for printing indicia upon a record card when the card is inserted into the mechanism comprising, in combination, a pivoted hammer assembly with a magnetic responsive armature and a hammer head, spring biasing means for resiliently maintaining said hammer head in an unlatched and suspended center position, hammer head cocking means comprising an electromagnet disposed to move said head off its center position against the force of said spring biasing means into a cocked position, a switch in series circuit with said electromagnet and switch levers associated therewith and actuated by insertion of said print card for energizing said electromagnet, release means to de-energize said electromagnet and thereby release said cocked hammer from said offcenter position comprising a lever secured to said hammer and operatively coupled to said switch levers whereby upon movement of said hammer head to its off-center position, said switch will be opened, and print means sufficiently spaced from said hammer head to permit insertion of said record card therebetween and so disposed thereto that upon release of said hammer head by said cocking means said hammer head springs past its normal center position by the force of said spring biasing means to punch said card against said print means.

5. The apparatus of claim 4 including a relay and a transferable relay contact normally connected electrically in series with said electromagnet and said switch whereby when said relay contact is transferred said relay energizes 10 to disable the energizing circuit to said electromagnet so long as said switch is closed during a printing cycle.

6. The apparatus of claim 5 including said triggering lever which when held operated during a printing cycle disables said switch lever and limits said electromagnet to a single energization.

7. The apparatus of claim 5 including a relay and a transferable relay contact normally connected electrically in series with said electromagnet and said switch whereby when said relay contact is transferred said relay energizes to disable the energizing circuit to said electromagnet so long as said switch is closed during a printing cycle.

8. A printing machine having a print mechanism for printing indicia upon a record card when the card is inserted into said machine comprising, in combination, a pivoted hammer frame, an electromagnet, a magnetically responsive armature and a hammer head fixed in said hammer frame, spring means for resiliently biasing said hammer frame in a home position, said spring having a bumper mounted at one end thereof for establishing said home position, hammer frame cocking means including said spring and said electromagnet, a switch connected electrically in series with said electromagnet, a triggering lever operated by insertion of said record card, a switch lever having a first tab and a second tab formed therefrom, a member on said first tab in operative arrangement with said switch for energizing said electromagnet to withdraw said armature and hammer frame while cocking said spring, means to maintain said switch lever in a neutral position, and print means spaced from said hammer head and record card whereby when said hammer frame is withdrawn said armature contacts said second tab on said switch lever causing said electromagnet to de-energize and release said hammer frame to the force of said cocked spring to eifect printing on said record card.

References Cited in the file of this patent UNITED STATES PATENTS 2,084,098 Long June 15, 1937 2,255,010 Lake Sept. 2, 1941 2,283,804 Grant et al. May 19, 1942 2,821,135 Larrabee Jan. 28, 1958 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3, 133 499 May 19,, 1964 Dominick Tringali It is hereby certified. that err ent requiring correction and th corrected below.

or appears in the above numbered pata,t the said Letters Patent should read as Column 10,, lines 3 and 7 for the claim reference numeral "5'' g each occurrence read 8 Signed and sealed this 3rd day of November 1964.

SEAL) LllBStZ ERNEST W. SWIDER' EDWARD J. BRENNER nesting Officer Commissioner of Patents 

1. A PRINT MECHANISM FOR PRINTING INDICIA UPON A RECORD CARD WHEN THE CARD IS INSERTED INTO THE MECHANISM COMPRISING, IN COMBINATION, A PIVOTED HAMMER ASSEMBLY INCLUDING A MAGNETIC-RESPONSIVE ARMATURE AND A HAMMER HEAD INTEGRAL THEREWITH, SPRING BIASING MEANS FOR RESILIENTLY MAINTAINING SAID HAMMER HEAD IN AN UNLATCHED AND SUSPENDED CENTER POSITION, HAMMER HEAD COCKING MEANS FOR EFFECTING A COCKING STROKE COMPRISING AN ELECTROMAGNET DISPOSED TO MOVE SAID HEAD OFF ITS CENTER POSITION AGAINST THE FORCE OF SAID SPRING BIASING MEANS INTO A COCKED POSITION, SWITCH ACTUATION MEANS RESPONSIVE TO INSERTION OF SAID CARD FOR ENERGIZING SAID ELECTROMAGNET, RELEASE MEANS INCLUDING A LEVER INTEGRAL WITH SAID HAMMER ASSEMBLY AND OPERATIVELY COUPLED DURING SAID COCKING STROKE TO SAID SWITCH ACTUATING MEANS FOR RELEASING SAID HAMMER HEAD FROM SAID COCKED POSITION, AND PRINT MEANS SUFFICIENTLY SPACED FROM SAID HAMMER HEAD TO PERMIT INSERTION OF SAID RECORD CARD THEREBETWEEN AND SO DISPOSED THERETO THAT UPON RELEASE OF SAID HAMMER HEAD FROM SAID COCKING MEANS SAID HAMMER HEAD SPRINGS PAST ITS NORMAL CENTER POSITION BY THE FORCE OF SAID BIASING MEANS TO PUNCH SAID CARD AGAINST SAID PRINT MEANS. 